Slewing ring of quality by the manufacturing precision of the slewing bearing itself,axial clearance,and heat treatment condition of the influence is very big,Here easy to be overlooked the factor is the influence of heat treatment condition.Obviously, making the raceway surface have no cracks and sag,requires the raceway surface with sufficient rigidity and outside, still must have enough depth of hardening layer and core hardness.
According to foreign information, depth of race hardening layer should thicken along with the roller increase, deepest more than 6 mm,the core hardness also should be higher, so just raceway have higher anti-pressure ability.So the slewing bearing raceway surface hardening layer depth insufficient,and the core hardness low, is also one of reasons the damage.